The oldest DNA ever sequenced came from the frozen remains of a horse more than half a million years old discovered in Canada’s west-central Yukon Territory. Thought to be an impossible project even by the coordinator, Dr. Ludovic Orlando of the University of Copenhagen, one of the many revelations included that the shared ancestors of all horses, donkeys and zebras lived more than four million years ago. “So basically we know that members of the genus Equus are at least twice as old as previously believed,” said Orlando…